A liquid crystal display panel mainly consists of an array substrate, a color filter substrate and a liquid crystal layer located between the array substrate and the color filter substrate. During manufacturing the liquid crystal display panel, a commonly adopted method is as follows: providing a sealant on a prepared array substrate first, then filling liquid crystal inside the sealant, and finally assembling the array substrate with the color filter substrate to form the liquid crystal display panel.
However, during manufacturing the liquid crystal display panel, the drop filling of the liquid crystal is insufficient due to the reasons such as drop volume error of the liquid crystal dropper, estimated liquid crystal volume being not enough. Thus, after the array substrate and the color filter substrate are assembled to form a cell, vacuum bubbles are generated in the cell, which will lead to a defect of display.